Typically, gas turbine engines include a compressor for compressing air, a combustor for mixing the compressed air with fuel and igniting the mixture, and a turbine blade assembly for producing power. Combustors often operate at high temperatures that may exceed 2,500 degrees Fahrenheit. Typical turbine combustor configurations expose turbine blade assemblies to these high temperatures. As a result, turbine blades must be made of materials capable of withstanding such high temperatures. In addition, turbine blades often contain cooling systems for prolonging the life of the blades and reducing the likelihood of failure as a result of excessive temperatures.
Typically, turbine blades, as shown in FIG. 1, are formed from a root portion and a platform at one end and an elongated portion forming a blade that extends outwardly from the platform. The blade is ordinarily composed of a tip opposite the root section, a leading edge, and a trailing edge. The inner aspects of most turbine blades typically contain an intricate maze of cooling channels forming a cooling system. The cooling channels in the blades receive air from the compressor of the turbine engine and pass the air through the blade. The cooling channels often include multiple flow paths that are designed to maintain all aspects of the turbine blade at a relatively uniform temperature. However, centrifugal forces and air flow at boundary layers often prevent some areas of the turbine blade from being adequately cooled, which results in the formation of localized hot spots. Localized hot spots, depending on their location, can reduce the useful life of a turbine blade and can damage a turbine blade to an extent necessitating replacement of the blade.
Conventional turbine blades may have one or more root turns, as shown in FIG. 2, which are located proximate to the root. Conventional root turns are typically curved elements of the flow path that change the direction of cooling fluid flow about 180 degrees in a serpentine formation in the root. While a conventional root turn successfully redirects cooling fluid flow from flowing spanwise towards a root to flowing spanwise towards the blade tip, a conventional root turn causes the cooling fluids flowing through the conventional root turn to undergo a significant pressure loss. Such a pressure loss often causes undesirable hot spots to develop in portions of the turbine blades. Thus, an internal cooling system having reduced pressure loss cooling fluid turns is needed.